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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <!-- 1.打印0-20之间的整数, 将每个数输出到控制台 -->

    <script>
        for (let i = 0; i <= 20; i++) {
            console.log(i)
        }

    </script>
</body>

</html>